The device (1) to use a tooth in order to discriminate the color of teeth, which comprises: a cellular telephone (2) with a photographic apparatus / digital camera (20) comprises an objective (21) and a light source (22) acting as a flash, a case (3), a spacer (7) mounted on the case in correspondence of the lens and of the light source, the first and second polarizing filters (4, 5) disposed inside the spacer, respectively on the lens and the light source, a label of the calibration (8) arranged in the spacer, a data base (100) containing a plurality of digital images of the sample which define unambiguously of the colors of the sample, and comparison software (101) to compare the digital image of the tooth engagement with the device (1) to the images of the sample of the data base (100) in order to discriminate the color of the tooth to be photographed.
